mcclellan



Sheet 1.

Attorney.

3 Sheets '0. D. MQOLELLAN.

ELECTRIC HEATER.

Patented Oct. 12, 1897.

THC NORRIS PEYERS 20.. PHo'ro-umb. wAsmNG'roN. u. A:v

(No Model.)

Witnesses (No Model.) 3 Sheets-Sheet 2. O. D. McCLELLAN.

ELECTRIC HEATER. No. 591,783. Patented Oct. 12,1897.

"IIIIIIIIIIIIIII'IIIVI Witnesses. Inventor Attorney.

(No Model.) 3 SheetsSheet 3. 0. D. MQCLELLAN.

ELECTRIC HEATER. No. 591,783. Patented Oct. 12,1897.

W itnesses. I nventor.

Attorney.

U TTED STATES PATENT @rrrcn.

OSCAR D. MCOLELLAN, OF PHILADELPHIA, PENNSYLVANIA, ASSIGNOR OF ONE-HALFTO FRANCIS DOUGHERTY, OF SAME PLACE.

ELECTRIC HEATER.

SPECIFICATION forming part of Letters Patent No. 591 ,783, dated October12, 1897.

Application filed October 17, 1895. Serial No. 565,936. (No model.)

To all whom it may concern:

Be it known that I, OSCAR D. MCOLELLAN, a citizen of the United States,residing in the city and county of Philadelphia and State ofPennsylvania, have invented certain new and useful Improvements inElectric Heaters, of which the following is a full, clear, and exactdescription, reference being had to the accompanying drawings, forming apart of this specification.

The object of this invention is to provide an apparatus for utilizingthe voltaic are for heating purposes, the same being especially, thoughnot exclusively, designed for the gen- I 5 eration of steam in boilers.

In carrying out my invention I produce the arc in a hermetically sealedcombustionchamber containing air, to the end that the burning of the arcshall consume the oxygen of the confined air and form carbonic acid,which, in conjunction with the unconsumed and inert nitrogen from theair, shall circulate around and convey the heat of the arc throughoutthe chamber. The carbonic acid thus formed prevents the candles burningtoo rapidly. The chamber may, however, be filled with an inert gas inthe first instance, its presence therein and not the manner in which itis obtained being the essential feature.

In the preferred embodiment of my invention the sealed chamber in whichthe heat is produced is arranged within the boiler orgenerating-chamber,and the electrodes within the sealed chamber are fedfrom a suitable source of electric energy,there being provided anintermediate rheostat, or controller, together with independent switchesfor the respective candles.

0 The electrodes are preferably of large capacity, being supported uponfire-brick or other refractory material within the combustion-chamber,as will hereinafter appear.

In the annexed drawings, Figure 1 is a ver- 5 tical section of asteam-boiler embodying my invention. Fig. 2 is a horizontal sectionthereof, as on the line a: w of Fig. 1. Fig. 3 is a diagram illustratinglthe electrical connections between the dynamo and the candles.

a modification.

Fig. 4 is a section similar to Fig. 1 0f 1 The numeral 1 designates aboiler or generating-chamber of any appropriate construction. In thepresent instance the boiler is an upright cylinder surmounted by theusual steam-dome 2. Arranged within this cylinder, near the bottomthereof, is a shallow cylindrical chamber 3, which is so disposed as tobe surrounded or jacketed by the water contained in the boiler; Risingfrom the chamber 3 is a series of vertical pipes t, which are preferablyconnected at their upper ends by cross-pipes 5. Confined within thechamber 3 is a series of heavy electric candles 6, the

electrodes of which are extended through heads 7, that are screwed intoor otherwise secured to tubes 8, that connect the walls of the twocylinders. The terminals of the electrodesare fitted to the heads 7,each pair of electrodes being suitably insulated from each other. Theelectrodes of the respective candles are electrically connected inseries with a suitable source of electric energy, the electrodes hereinshown being of the parallel type wherein no regulating mechanism isrequired for automatically adjusting the points of the electrodes'inrespect to each other. I

would remark, however, that so far as the spirit of the invention isconcerned the same is not affected by any particular type of candles,nor by the number of candles employed.

In the present instance the conductors to the respective candles areconnected with switches 9, whereby any or all of the candles may bethrown into or out of circuit, as desired. There are also providedintermediate the dynamo 10 and the candles arheostat 11, by means ofwhich the current transmitted to the candles may be controlled, and alsoa storage battery 12 and a switch-board 13, the

varying the strength of the electric current through the medium of therheostat. The

burning of the are within the hermeticallysealed chamber consumes theoxygen of the confined air and forms carbonic acid, which, inconjunction with the unconsumed and inert nitrogen from the air in thechamber, circulates around and conducts the heat of the arc throughoutthe combustion ehamberviz., the cylinder 3 and its pipes t and 5. Thecarbonic acid and the nitrogen being indestructible, and being confined,an intense heat is produced with the maximum economy, and this withoutthe emission to the external atmosphere of smoke or other deleteriousprodncts of combustion.

The caloric produced within the chamber is imparted from the walls ofthe latter to the surrounding water, from which steam is generated. Thiswater prevents the walls being injuriously affected by the intense heat.

During the operation of the apparatus the storage battery 12 is switchedinto circuit, so as to store up sufficient electric energy to feed thecandles preparatory to the subsequent starting of the dynamo.

I preferably arrange in the bottom of the chamber 3 a bed of fire-brick3 or other refractory material, upon which the heavy electrodes aresupported. This material also absorbs heat to a large extent and formsan increased area for its dissipation. It also serves as a conductor ofheat to the bottom and lower lateral portions of the chamber orreceptacle.

In Fig. 4 is shown a modification of the apparatus, wherein, as will beobserved, the combustion-chainber comprises a vertically disposedcylinder 3, arranged concentrically within the boiler, so as to form anannular water-containing chamber. The lower end of the cylinder isprovided with a manhole ll, whereby access to said cylinder may bereadily had. This manhole is equipped with a cap or cover 15, by meansof which the cylinder may be hermetically sealed. Confined within thecylinder, at various points in the length, are the electric candles (3,the elecsemss trodes whereof are extended through duct-s or tubes 8,that connect the walls of the two cylinders, the outer ends of saidtubes or ducts being hermetically sealed by means of plugs to which therespective terminals of the electrodes are fitted.

I claim 1. A heater comprising a gas-tight receptacle, carbon pointsarranged therein, and an inert gas filling said chamber and designed tocirculate therein, substantially as specified.

2. A heatercomprising a gas-tight receptacle, carbon points arrangedtherein, a bed of refractory material, and an inert gas filling saidchamber and designed to circulate there in, substantially as specified.

A heater comprising a gastight chamber or receptacle having a number oftubes radiating therefrom, carbon points arranged in said chamber orreceptacle, and an inert gas filling the same and designed to circulatetherein, substantially as specified.

t. A heater comprising an inner gas-tight receptacle, carbon pointsarranged therein, an inert gas filling said receptacle and dc signed tocirculate therein, and an outer receptacle separated from said innerreceptacle by a heating space or chamber, substantially as specified.

5. A heater comprising an inner gas-tight receptacle containing an inertgas designed to circulate therein, an outer or surrounding receptacleseparated from the inner receptacle by a heating space or chamber, anumber of tubes extending through the walls of both said receptacles,and carbon candles or points arranged in said tubes and extending intothe inner receptacle, substantially as speci lied.

In testimony whereof I have hereunto af.- fixed my signature in thepresence of two s ubscribing witnesses.

OSGAR D. MGCLELLAN.

Witnesses:

JOHN R. NOLAN, ANDREW F. mourn.

